But it adds that “his authority has not prevailed against the currency of the spelling with sc, due to erroneous association with L. scindere to cut.”

Getting back to the end of the word, the “th” in “scythe” was indeed pronounced in the 18th and 19th centuries, according to several editions of John Walker’s pronouncing dictionaries (the entries are labeled “SITHE, or SCYTHE”).

In checking a 1791 edition of Walker’s A Critical Pronouncing Dictionary and Expositor of the English Language, though, we found a surprise.

The word “sigh” apparently was sometimes pronounced much like “scythe”!

In a note attached to his entry for “SIGH,” Walker notes that a “very extraordinary pronunciation of this word prevails in London, and, what is more extraordinary, on the Stage.”

He describes this pronunciation as “so different from every other word of the same form as to make it a perfect oddity in the language.”

“This pronunciation approaches to the word scythe,” he adds, “and the only difference is that scythe has the flat aspiration as in this; and sigh the sharp one, as in thin.”

Walker goes on to condemn this pronunciation as a “palpable contempt of orthography.”

He may have been unaware that in an old British dialect, a verb spelled and pronounced like “sithe” was a variant of “sigh.”

The OED has citations for this use of “sithe” at various periods ranging from about 1275 to 1875.

One example of its use in print comes from William Holloway’s A General Dictionary of Provincialisms (1838): “I knew a clergyman who always read ‘Sithing,’ for ‘sighing of a contrite heart.’ ”

The OED describes this usage as a remnant of a long dead verb, siche, which dated back to the ninth century and also meant “sigh.”

In fact, siche may have been the ancestor of “sigh,” which actually came along later, sometime before 1300.

When siche became obsolete in the 1400s, the OED says, its past tense forms became associated with the newer “sigh” and remained in use.

So what sounded to Walker like a mispronunciation of “sigh” as “sithe” was actually the dying gasp of a much older verb—and one more example of how language changes as time goes by.